1. Field of the Invention
The invention is directed to a pump, especially a drum pump or barrel pump with a pump rotor which is drivable by a motor via a rotor shaft, by means of which pump rotor the liquid in a ring channel can be pumped up to an outlet connected with the ring channel, this ring channel lying between a supporting pipe having a bearing for the rotor shaft and a tubular housing jacket which form a pump pipe set, wherein the liquid can be sucked up by the pump rotor through an inlet formed in a pump base connected with the housing jacket, and wherein an arrangement for protecting against ascending liquid in the supporting pipe is provided in the lower part of the pump pipe set.
2. Description of the Related Art
In barrel pumps of this type, the arrangement for protecting against ascending liquid can either be formed of a sliding ring seal or can comprise a leakage channel connecting the supporting pipe with the outside of the housing jacket, the liquid ascending in the supporting pipe being drained outward through this leakage channel.
A barrel pump with a sliding ring seal is known, for example, from DE 37 18 325 C2 and a barrel pump with a leakage channel is known, for example, from DE 27 50 801 C2.
The decision about whether to use a pump with a sliding ring seal or with a leakage channel depends on operating factors and often cannot always be determined before such barrel pump is procured. A wrong decision will result in frequent breakdowns and repairs. In many cases, a pump with another type of protection against ascending liquid will have to be acquired. All of this leads to increased costs.